The present invention relates to a method of manufacturing a magnetic head, and more precisely relates to a method of manufacturing a magnetic head, which is capable of preventing an element or elements from being damaged by static electricity which is generated while manufacturing the magnetic head.
The magnetic heads for magnetic disc drive units are manufactured by the steps of: forming magnetizable film layers and non-magnetizable film layers on a surface of a ceramic substrate, which is formed into a wafer; and patterning the film layers. To execute the patterning step, first a resist layer is formed on the film layers and formed into prescribed patterns, then the film layers, which are masked with the patterned resist layer, are patterned by ion milling, sputtering, etc.
While executing treatments of the film layers, e.g., trimming by ion milling, pattern etching by dry etching, cleaning the surface of the film layers by sputter-etching, static electricity is charged on the surface of the film layers; the static electricity damages sensing parts of element sections of the magnetic heads and badly influences characteristics of the magnetic heads. To solve these disadvantages, an ion milling device neutralizes ions so as not to charge the static electricity in a work piece.
In the conventional method of manufacturing the magnetic head, damaging the element sections by static electricity was not a serious problem. However, in the case of spin valve heads capable of writing data with high density, the element sections are apt to be damaged by static electricity, so it is necessary to protect the element sections from the static electricity. In conventional magnetic heads, about 20 [V] of static electricity damages the element sections; in spin valve heads, about 5 [V] of static electricity damages the element sections.
In some cases, the film layers are etched to form into a plurality of isolated islands, so influences of static electricity must be prevented.